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Four Common Quality Defects in Steel Structure Welding

2021-01-07

One of the main connection methods of steel structure is welding, the quality of steel structure installation is determined by the quality of welding. There is research that has found the following four quality defects:

  1. Cracks:

Commonly cracks can be divided into hot cracking and cold cracking. The reasons that caused hot cracking to include the materials of bad anti-crack ability, unreasonable weld layout, incorrect parameter, etc. The main causes of cold crack are unreasonable welding structure design, improper welding seam arrangement, non-preheating before welding and fast cooling after welding, etc. The treatment method is to drill the crack or eradicate the weld metal at the crack at both ends for repair welding.

( the picture of welding details)

  1. Slag inclusions:

The main reasons for slag inclusion are poor welding material quality, too small welding current, extremely fast welding speed, multi-layer welding slag that has not been cleaned up, etc., the treatment method is to remove the weld metal at the slag inclusion place, and then welding repair.

  1. Non-fusions:

The main causes of non-fusion are too small welding current, too fast welding speed, too small groove Angle clearance, poor operation technology, etc. The treatment method for the unfused is to eliminate the weld metal at the unfused spot after welding repair.

  1. Weld beading:

The main causes of welding nodules are an incorrect selection of welding parameters, poor operation techniques, and improper placement of welding parts. The treatment method is to remove the excess accumulation of metal by hand or by mechanical means such as a shovel, file and grinding.

Through the introduction of the above content, we understand the four common quality defects in steel structure welding, and also know the corresponding treatment methods.